[Triangular skull. Apropos of trigonocephaly].

The authors present 87 patients with trigonocephaly who were operated on. They take an interest in the consequence of the early synostosis of the metopic suture. The metopic suture combine with the sagittal sutural system, but his spot of manifestation is unambiguous. Its manage the dimension of the frontal bone which himself has repercussions on the set of the orbits. Thereby the fronto-orbito-facial dysmorphy has two component parts. One direct with little frontal bone and a thick sutural spot which extend more or less to the bregma and a second indirect with early deformation of the orbits and late deformation of the parietal bones. Three clinical patterns are described: micro-frontal shape, medio-frontal shape and orbito-frontal shape. In the pure shapes there is no direct impact on the encephalon but the venous stasis is high and probably liable for the encephalic damage when they exist. A single surgical proceeding does not meet the many varieties of deformations. Resection of fused metopic suture from a bifrontal flap; confection of orbito-fronto-nasal band which is opened by greenstick fracture on the metopic site; transposition of an hemicoronal suture between the two hemifrontal valves lateraly translated; foreward mobilisation and interventing temporal flaps. To finish the modeling it is necessary to open the periosteum sheet in order to translate temporal muscles then to overlay with interparietal pedicularly periosteum the anterior step. Metopic synostosis is ordinarily only an aesthetic deformity infrequently associated with intracranial pathology. The treatment must be required for pronounced deformities to prevent significant psychosocial consequences.